Method of assembling and bonding a laminated liner within a closure member

ABSTRACT

This disclosure relates to a novel packaging method which includes the steps of packaging a product into a container having a mouth defined by a lip, inserting a metallic-nonmetallicmetallic laminated liner upon the container lip in sandwiched relationship between the container lip and an end panel of an associated closure, and inducing heat in the metallic ply sufficient to fuse one of the metallic plies to the closure end panel and the other of the metallic plies to the container lip. Preferably the bond strength between the other of the metallic plies and the container lip is great enough to resist delamination upon the removal of the closure to thus provide an inner seal. Additionally, the bond strength between the one metallic ply and the end panel is sufficiently strong to retain the nonmetallic ply with the closure upon the removal thereof whereby the nonmetallic ply can be used for resealing purposes after the closure has been once removed from the container.

Pollock et al.

' United States Patent MEMBER Inventors:

Assignee:

Filed:

App]. No.:

METHOD OF ASSEMBLING AND BONDING A LAMINATED LINER WITHIN A CLOSUREWilliam J. Pollock, Glenview; Peter Tagalakis, Chicago, both of I11.

Nov. 30, 1973 Related US. Application Data Division of Ser. No.-287,825, Sept, 11, 1972, Pat. No. 3,815,314.

US. Cl. 156/272; 156/69; 215/241;

215/349; 428/45; 428/64 Int. Cl. B29C 27/04; B32B 3/02; B65D 53/04 Fieldof Search 161/41-43;

References Cited UNITED STATES PATENTS Taliaferro 215/349 X CarvalhoClark Weisgerber \NSERT LAMINATE PLACE CAP v .1

STEP 1 STEP '2 FOREIGN PATENTS OR APPLICATIONS 474,880 11/1937 UnitedKingdom 215/349 Primary ExaminerPhilip Dier Attorney, Agent, orFirmDiller, Brown, Ramik & Wight [57] ABSTRACT This disclosure relatesto a novel packaging method which includes the steps of packaging aproduct into a container having a mouth defined by a lip, inserting ametallic-nonmetal]ic-metallic laminated liner upon the container lip insandwiched relationship between the container lip and an end panel of anassociated closure, and inducing heat in the metallic ply sufficient tofuse one of the metallic plies to the closure end panel and the other ofthe metallic plies to the container lip. Preferably the bond strengthbetween the other of the metallic plies and the container lip is greatenough to resist delamination upon the removal of the closure to thusprovide an inner seal. Additionally, the bond strength between the onemetallic ply and the end panel is sufficiently strong to retain thenonmetallic ply with the closure upon the removal thereof whereby thenonmetallic ply can be used for rescaling purposes after the closure hasbeen once removed from the container.

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DU M0440 METHOD OF ASSEMBLING AND BONDING A LAMINATED LINER WITHIN ACLOSURE MEMBER This is a Divisional filing of application Ser. No.287,825 in the name of William J. Pollock and Peter Tagalakis, entitledPACKAGING METHOD, filed on Sept. 11, 1972 and now US. Pat. No.3,815,314.

An object of this invention is to provide a novel method of packaging aproduct in a container having a mouth defined by a lip which includesconstructing a metallic-nonmetallic-metallic laminated liner andinserting the same in sandwiched relationship between the container lipand an end panel of an associated closure, and inducing heat in themetallic ply sufficient to fuse one of the metallic plies to the closureend panel and the other of the metallic plies to the container lip.

In keeping with a more specific aspect of the novel invention, a furtherobject includes the steps heretofore described wherein the one metallicply is fused to the closure end panel with a first bond strength greaterthan a second bond strength between the one metallic ply and thenonmetallic ply and a third bond strength between the other metallic plyand the nonmetallic laminate, and the other metallic ply is fused to thecontainer lip with a fourth bond strength greater than the first throughthe third bond strengths, thus providing difi'erential delamination ofthe liner upon removal of the closure from the associated container.

In keeping with a further object of this invention the third bondstrength is weaker than the first, second and fourth bond strengthswhereby upon the removal of the closure the liner will delaminatebetween the other metallic ply and the nonmetallic ply.

Still another object of this invention is to provide a novel packagingmethod wherein the first and second bond strengths are greater than thethird bond strength whereby upon the removal of the closure the onemetallic ply and the nonmetallic ply will remain adhered to the closureend panel.

In keeping with another aspect of this invention. a prepackaging methodis provided which includes the steps of providing a closure having anend panel and a peripheral skirt, providing a liner as at least ametallicnonmetallic-ply, assembling the liner within the closure withthe metallic ply proximate the closure end panel, and inducing heat inthe metallic ply sufficient to fuse the same to the end panel wherebyduring subsequent handling, storage, shipment, etc. the components willnot accidentally and/or inadvertently disunite.

Still another object of this invention is to provide a novelprepackaging method wherein the united closure and liner are shipped toa packager with the latter providing a container having a mouth definedby a lip, packaging a product in the container, and assembling theclosure upon the container with the nonmetallic ply upon the containerlip.

Still another object of this invention is to provide a novelprepackaging method of the type immediately aforesaid wherein the lineris mechanically retained within the closure prior to the heat inducingstep, said retaining step being performed by either adhesive bonding themetallic ply to the closure end panel and- /or by mechanicallyinterlocking the periphery of the liner within the closure.

Still another object of this invention is to provide a novelprepackaging method which includes the steps of providing a closurehaving an end panel and a peripheral skirt, providing a liner as atleast a metallic-nonmetallic-metallic laminate, assembling the linerwithin the closure with one of the metallic plies proximate the closureand panel, inducing heat in the one metallic ply sufficient to fuse theone metallic ply to the end panel, whereby during subsequent handling,storage, shipment, etc. the components will not accidentally disunite,thereafter shipping the united closure and liner to a packager,providing a container having a mouth defined by a lip, packaging aproduct in the container, assembling the closure upon the container withthe other metallic ply proximate the container lip, and thereafterinducing heat at least in the other metallic ply sufficient to fuse thesame to the container lip.

A further object of this invention is to provide a novel methodincluding the steps immediately heretofore set forth and furtherincluding the step of mechanically retaining the liner in the closureprior to the heat inducing step, the retaining step being performed byadhesive bonding the one metallic ply to the closure end panel and/ormechanically interlocking the periphery of the liner within the closure.

A final object of this invention is to provide a novel liner for aclosure comprised as a disc-like laminated body including a nonmetallicply, and adhesive on opposite faces of the nonmetallic ply, and ametallic ply bonded by the adhesive to each of the opposite faces, andthe bond strength of the adhesive between one of the metallic plies andthe nonmetallic ply being greater than the bond strength of the adhesivebetween the other of the metallic plies and the nonmetallic ply wherebyupon being adhered to a container by heat induced in the liner and thesubsequent removal therefrom the liner will delaminate between thenonmetallic and said other metallic plies.

With the above and other objects in view that will hereinafter appear,the nature of the invention will be more clearly understood by referenceto the following detailed description, the appended claimed subjectmatter, and the several views illustrated in the accompanying drawing.

IN THE DRAWING FIG. 1 is an exploded fragmentary view partially in sideelevation and partially in cross section, and illustrates the steps ofone packaging method of this invention including those of inserting alaminated liner into a closure, assembling the closure with a packagedcontainer, assembling the closure and packaged container, and thereafterincluding heating the liner to adhere the same to a lip of the containerand an end panel of the closure.

FIG. 2 is a highly enlarged fragmentary sectional view of the encircledportion appropriately identified in FIG. 1, and illustrates thelaminated construction of the liner.

FIG. 3 is an enlarged fragmentary sectional view of the correspondingencircled portion of FIG. 1 and illustrates the manner in which theliner of FIG. 2 is mechanically retained within the closure adjacent anend panel thereof.

FIG. 4 is a fragmentary enlarged sectional view of the associatedencircled portion of FIG. 1, and illustrates the manner in which aperipheral or circumferential portion of the liner is compressed uponthe assembly of the closure upon the container.

FIG. 5 is an enlarged fragmentary sectional view corresponding to theencircled portion of FIG. I, and illustrates the manner in which theliner is fused to the closure end panel and the container lip by virtueof the heat induced therein.

FIG. 6 is a fragmentary sectional view similar to FIG. 5, butillustrates the manner in which one of the metallic plies remainsadhered to the container lip upon the removal of the closure therefromdue to differential bond strengths between various plies of thelaminate, the closure and the container lip.

Before describing the novel methods of this invention, reference isfirst made to FIG. 2 of the drawing which illustrates a liner formed asa laminated body 10 of a generally circular configuration. The liner orbody 10 includes a laminate formed of a plurality of plies 11 through17, although variations may be made therein, as will be describedfurther herein.

The centermost ply 11 is constructed of nonmetallic material, preferablypulpboard or similar paper stock material, and is generally the thickestof the plurality of plies. The ply 11 is formed from generallyresilient, compressible material which functions to assure intimatecontact between an associated closure end panel and container lip, aswill be described more fully hereinafter, incident to a heat sealingoperation. The resilient nature of the ply 11 is also of particularimportance for rescaling purposes, again as will be describedhereinafter.

The adhesive 12, 13 is applied in a conventional manner to 'respectiveopposite faces or surfaces 20, 21 of the nonmetallic ply 11. The purposeof the adhesives 12, 13 is to adhere to the nonmetallic ply 11 therespective plies 14, 15.

The plies 14, 15 are constructed from metallic foil material as, forexample, aluminum foil or any other material which can be heated byinduction when positioned in an appropriate electric field. The foilmust not only be capable of being heated by induced energy, but the foil15 must be impermeable inasmuch as it functions as a seal, as will benoted fully hereinafter.

Depending upon the particular materials involved the liner 10 may or maynot require the coatings 16, 17 which are conventional copolymer resinssuch as, polyethylene, copolymer polyethylene, ionomer resin, waxresinhot melts or other types of resins or adhesives which are activated byheat, the function being that of bonding the metallic plies l4, 15 to aclosure end panel and a container lip, respectively. In addition thecopolymer coating 16 may be spot-coated with an adhesive to temporarilyretain the liner within an associated closure or the coating 16 may beomitted and the adhesive applied directly to the metallic ply 14 for thesame purpose. In lieu of the mechanical connection achieved by theadhesive or in order to augment the same the closure may be providedwith a circumferential bead about the periphery of its peripheral skirtto additionally assure that the liner cannot be accidentally and/orinadvertently dislodged therefrom, again as will be describedimmediately hereinafter.

Reference is now made to FIG. 4 of the drawing which illustrates aconventional container preferably constructed from polymeric and/orcopolymeric material, although glass and metal may be employed, thecontainer body being generally designated by the reference numeral andbeing constructed to include an external thread or a plurality of lugs26 and an upper most terminal scaling lip 27. The container 25 may beconstructed from polyethylene as might be a closure 30 having an endpanel 31 and a peripheral skirt 32 whose thread 33 or lugs cooperatewith the thread 26 or lugs to maintain these components in conventionalassembled relationship. A radially inwardly directed circumferentialbead 34 functions to retain the liner 10 within the closure 30immediately adjacent an inner face 35 of the end panel 31.

Reference is now made to FIG. 1 of the drawing which from left to rightillustrates four steps identified as STEP 1 through STEP 4.

Considering STEP 1 of the method illustrated in FIG. 1, the liner 10 isfirst assembled into the closure 30 with the copolymer resin coating 16immediately adjacent and against the surface 35 ofthe end panel 31, asis best shown in FIG. 3. Depending upon the materials involved thecopolymer resin coating 16 may be eliminated or, if found necessary ordesirable, a spot-coating of an adhesive atop the coating 16 may beemployed to temporarily retain the liner 10 within the closure 30 priorto the heat sealing operation. In conjunction with or in lieu of theadhesive the closure may be provided with the retaining bead 34, in themanner heretofore described. The assembled closure and container arebest shown in FIG. 3 whereafter this assembly is united in STEP 2 ofFIG. 1 in a Conventional manner by conventional capping machinery tothread or otherwise secure the closure upon the container. Reference ismade to FIG. 4 whereat the closure 30 is shown fully seated upon thecontainer 25 with the capping force being sufficient to compress thenonmetallic ply 11 in the area of the container lip 27. The nonmetallicply 11 may be constructed from pulpboard, cork. plastics such aspolystyrene and polyethylene foam, rubber, etc.

In STEP 4 there is illustrated a high frequency heater 40 havingsuitable induction coils 41 coupled by leads 42, 43 to a source ofelectrical energy (not shown). Upon being subjected to the electricalfield generated by the high frequency induction heater 40 the plies orfoils 14, 15 are heated to an appropriate temperature depending, ofcourse, upon the characteristics of the material thereof, those of theresin coatings 16, 17, and the materials of the closure 30 and container25. As the temperature of the metallic plies 14, 15 is increased thecopolymer resin coatings 16, 17 become heated sufficiently to bond theliner to the surface 35 of the end panel 31 of the closure 30 and to thecontainer lip 27 of the container 25, respectively. The bonds thuscreated are best illustrated in FIG. 5. In this same figure areindicated bonding layers between the various plies having varied bondstrengths, the same being indicated by the reference characters BS (bondstrength) 1, BS (bond strength) 2, BS (bond strength) 3, and BS (bondstrength) 4. Considering the latter first, the bond strength BS4 betweenthe metallic ply 15 and the container lip 27 is such as to assure thatthe ply 15 will remain adhered to the container lip 27 when the closure30 is removed, as is best illustrated in FIG. 6. Moreover. the bondstrength BS3 of the adhesive 13 is less than that of the bond strengthBS4 whereby upon the removal of the closure 30, as again shown in FIG.6, delamination will occur between the metallic ply 15 and thenonmetallid (pulpboard) ply 11. Due to this relative bond strengthdifferential (between bond strengths BS3 and BS4) the metallic ply 15remains adhered to the container lip 27 and serves as an inner seal uponthe removal ofthe closure 30 whereas the ply 11 will function as areclosure seal after the ply 15 has been removed and the closurereclosed upon the container. However, in order to assure that the pliesll, 14 remain adhered to the closure 30 upon the removal thereof therespective bond strengths BS2 and BS1 are greater than the bond strengthBS3 but less than the bond strength BS4. Thus upon the removal shown inFIG. 6 the ply 14 remains adhered to the inner face 35 of the closure 30and also adhered thereto through the adhesive 12 is the nonmetallic ply11. In this manner the plies l1, 14 cannot be lost or dislodged upon theremoval of the closure 30 after the heat sealing operation andreclosures can be performed in a repetitive manner with a seal beingachieved between the container lip 27 and the ply 11, upon, of course,the removal and discarding of the inner seal 15.

In keeping with another aspect of this invention, the liner may beconstructed to include only the components l1, 12, 14 and 16 with thecomponents 13, 15 and 17 being omitted. By practicing the methodheretofore described relative to FIG. 1 the induced heating of STEP 4results in the fusion of the copolymer resin ply 16 to the end panel 31of the closure 30, but due to the absence of the plies l3, l5 and 17 thenonmetallic ply 11 is merely compressed at the container lip 27 but doesnot adhere thereto. Liners of this type are used wherein it isunnecessary for the contents to be sealed in a hermetic fashion, as isaccomplished by the impermeable foil ply 15 in conjunction with themethod of FIG. 1.

In keeping with yet another aspect of this invention, the liner 10 maybe constructed to include only the components 11, 12, 14, 16 and eitherof the components 13 or 17, but not the metallic ply 15. In this case,assuming that the components 15, 17 have been omitted, the coating 13may be, for example, vinyl, etc. adhered to the pulp ply 11. However, bypracticing the method heretofore described relative to FIG. 1 theinduced heating of STEP 4 results in the fusion of the ply 16 to the endpanel 31, but due to the absence of the ply 15 the nonmetallic ply 13will not adhere to the container lip 27.

In further keeping with this invention the liner 10 may be constructedto include all components illustrated in FIGS. 5 and 6 except thecoating 17. Here again the ply 15 is constructed of lead, tin, aluminumfoil, or similar metallic material and though the same heats up whensubjected to the induction field (STEP 4) the ply 15 will not adhere tothe container lip 27 since it is uncoated or devoid of the adhesivecoating 17.

In further accordance with this invention the method of FIG. 1 can beaugmented by the inclusion of another induction heating step after theliner and closure have been assembled, but prior to the shipping thereofto the packager and the eventual capping of the container.

. For example, after the liner has been inserted into the closure inkeeping with STEP 1 and assembled as shown in FIG. 3, the closure andliner in the absence of the container and its product may be subjectedto an induction heating operation resulting in the bonding of the foilply 14 of the inner surface of the end panel 31 of the closure 31. Inthis manner when a plurality of the closures 30 are shipped from themanufacturer to the packager there is far less likelihood that theliners 10 will become accidentally and/or inadvertently disunited fromthe closure 30.

In addition to the foregoing descriptions of the pri mary embodiment ofthis invention and the modifications thereof, it is also intended inkeeping with this invention to construct the closure or cap 30 from metallic rather than nonmetallic material. Obviously a metallic cap willbe heated in the induction field of STEP 4 and such heat will betransferred by conduction to a liner, be it metallic or nonmetallic, andto adhering type coating thereon as, for example, the coating 17 uponthe laminate 15 to achieve the seal at the container lip 27 or similarlyachieving a bonding between the coating 16 and the internal surface 35of the metallic cap 30.

While preferred forms and arrangements of parts have been shown inillustrating the invention, it is to be clearly understood that variouschanges in details and arrangement of parts may be made withoutdeparting from the spirit and scope of this disclosure.

We claim:

1. A prepackaging method comprising the steps of providing a closurehaving an end panel and a peripheral skirt, providing a liner formed ofat least a metallic ply nonmetallic ply metallic ply laminate,assembling the liner within the closure with one of the metallic pliesproximate the end panel, electrically inductively heating said onemetallic ply sufficient to fuse said one metallic ply to the end panelwhereby the liner and closure will become fusibly united, and saidelectrically inductively heating step creates a bond strength betweenthe one metallic ply and the end panel and the nonmetallic ply which isgreater than the bond strength between the remaining metallic ply andthe nonmetallic ply whereby upon removal of the closure from anassociated container the remaining metallic ply will be retained uponthe container and separation of the liner will occur between aninterface of the nonmetallic ply and the remaining metallic ply.

2. The method as defined in claim 1 including the step of mechanicallyretaining the liner in the closure prior to the performance of theelectrically inductively heating step.

3. The method as defined in claim 1 including the step of mechanicallyretaining the liner in the closure prior to the performance of theelectrically inductively heating step, said retaining step beingperformed by adhesive bonding said one metallic ply to the closure endpanel prior to the performance of the electrically inductively heatingstep.

4. The method as defined in claim 1 including the step of mechanicallyretaining the liner in the closure prior to the performance of theelectrically inductively heating step, said retaining step beingperformed by mechanically interlocking the periphery of the liner withinthe closure prior to the performance of the electrically inductivelyheating step.

1. A PREPACKAGING METHOD COMPRISING THE STEPS OF PROVIDING A CLOSUREHAVING AN END PANEL AND A PERIPHERAL SKIRT, PROVIDING A LINER FORMED OFAT LEAST A METALLIC PLY-NONMETALLIC PLY -METALLIC PLY LAMINATE,ASSEMBLING THE LINER WITHIN THE CLOSURE WITH ONE OF THE METALLIC PLIESPROXIMATE THE END PANEL, ELECTRICALLY INDUCTIVELY HEATING SAID ONEMETALLIC PLY SUFFICIENT TO FUSE SAID ONE METALLIC PLY TO THE END PANELWHEREBY THE LINEAR AND CLOSURE WILL BECOME FUSIBLY UNITED AND SAIDELECTRICALLY INDUCTIVELY HEATING STEP CREATES A BOND STRENGTH BETWEENTHE ONE METALLIC PLY AND THE END PANEL AND THE NONMETALLIC PLY WHICH ISGREATER THAN THE BOND STRENGTH BETWEEN THE REMAINING METALLIC PLY ANDTHE NONMETALLIC PLY WHEREBY UPON REMOVAL OF THE CLOSURE FROM ANASSOCIATED CONTAINER THE REMAINING METALLIC PLY WILL BE RETAINED UPONTHE CONTAINER AND SEPARATION OF THE LINER WILL OCCUR BETWEEN ANINTERFACE OF THE NONMETALLIC PLY AND THE REMAINING METALLIC PLY.
 2. Themethod as defined in claim 1 including the step of mechanicallyretaining the liner in the closure prior to the performance of theelectrically inductively heating step.
 3. The method as defined in claim1 including the step of mechanically retaining the liner in the closureprior to the performance of the electrically inductively heating step,said retaining step being performed by adhesive bonding said onemetallic ply to the closure end panel prior to the performance of theelectrically inductively heating step.
 4. The method as defined in claim1 including the step of mechanically retaining the liner in the closureprior to the performance of the electrically inductively heating step,said retaining step being performed by mechanically interlocking theperiphery of the liner within the closure prior to the performance ofthe electrically inductively heating step.